The present invention relates to an eddy current correction method and magnetic resonance imaging apparatus, and more particularly to a method of correcting an effect by eddy current on a gradient magnetic field, and a magnetic resonance imaging apparatus comprising eddy current correcting means.
In a magnetic resonance imaging apparatus, a corrective signal is appended to a gradient magnetic field signal to correct an effect by eddy current on a gradient magnetic field generated by a gradient magnetic field generating apparatus (for example, see Patent Document 1). The appending of the corrective signal for correcting eddy current of short time constant is sometimes referred to as pre-emphasis. This term is derived from a technique of, allowing for weakening of the waveform of an effective gradient magnetic field due to an effect by eddy current, emphasizing the waveform beforehand.
[Patent Document 1]
Japanese Patent Application Laid Open No. 4-22338 (Pages 3-4, FIGS. 2-3)
However, the pre-emphasis sometimes cannot be done as required because of the output limit of a gradient power supply or the like, so that it becomes impossible to perform the eddy current correction properly.